JPS61168658A - Unsaturated polyester resin composition for treatment of cathode ray tube - Google Patents

Abstract

PURPOSE:To provide the title resin compsn. which has a low viscosity and excellent transparency and adhesion and does not cause distortion during curing, by dissolving an unsaturated polyester in styrene (derivative) and (meth)-acrylic acid (derivative). CONSTITUTION:An unsaturated polyester (A) having an MW of 500-8,000 per mol of unsaturated group, obtd. by reacting an acid component contg. an unsaturated dibasic acid (anhydride) (e.g. maleic anhydride) and optionally other polybasic acid with an alcohol component, is dissolved in styrene (derivative) (B) and (meth) acrylic acid (derivative) (C) in such a proportion as to give a ratio of a/(b+c) of 1/30-1/1 and b/c of 1/10-10/1, wherein a, b and c are moles of unsaturated groups of components A, B and C, respectively, thus obtaining the desired unsaturated polyester resin compsn. for the treatment of a cathode ray tube.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an unsaturated polyester resin composition for cathode ray tube processing.

(Prior art) A cathode ray tube with a front glass bonded has a structure as shown in Figure 1, and the front surface of the cathode ray tube is made of an unsaturated polyester resin composition,
The front glass is bonded using an epoxy resin composition.

That is, as shown in FIG. 1, a screen glass 3 having the same curvature and the same size as the face plate part 2 of the cathode ray tube 1 is surrounded and held by a tape 4 at a minute interval, and the screen glass 3 is surrounded by a tape 4 in this gap. This is a method of filling a resin composition 5 to form an electrode ray tube 6 with a front glass.

Conventionally, epoxy resin compositions and unsaturated polyester resin compositions have been used as this resin composition, but each has advantages and disadvantages, and a resin composition for front glass bonding that satisfies both properties and workability. The current situation is that this has not been obtained.

For example, epoxy resin compositions have strong adhesive strength and are convenient for adhering the front glass to the face plate, but due to their nature, they have a considerable coloring property. It's not good for things that are important. Furthermore, for products such as color cathode ray tubes, where the tube itself has high added value, recycling is also important.
In the case of epoxy resin, the adhesive strength is strong, so it is easy to damage the faceplate part when removing the front glass.

It is nearly impossible to remove this glass.

Furthermore, since epoxy resin compositions have a higher viscosity than unsaturated polyester resin compositions, they have the disadvantage that bubbles that are mixed in during mixing of a curing agent or injection of resin are difficult to remove. Moreover, the viscosity of epoxy resin increases rapidly immediately after mixing with the hardening agent, so the pot life for injection is very short, and special mixing equipment and injection equipment are required to perform the work smoothly, resulting in poor workability. Very poor.

On the other hand, in unsaturated polyester resin compositions.

The viscosity is generally relatively low, a few poise, and it is difficult to mix curing agents,
It is easy to inject resin between the cathode ray tube face plate and the front glass, and its viscosity is low.

Although it has advantages such as good foam film cleaning during mixing and injection, if the ratio of the curing agent used in the unsaturated polyester resin composition changes from the specified conditions, curing distortion may occur locally during curing. This hardening distortion becomes a lens effect when the cathode ray tube is operated.

It appears as stripes or bright spots on the screen.

These striped patterns and bright spots impair the value of the product, so e! It is necessary to be careful about the mixing ratio of the curing agent.

In addition, since curing distortion occurs due to rapid heating or uneven temperature of the curing furnace, sufficient temperature control must be carried out.

Unsaturated polyester resin compositions have many production problems as mentioned above, but they have low viscosity, easy bubble removal, and 9
Excellent transparency with little M color.

Furthermore, although its adhesive strength is weaker than that of epoxy resins, it is sufficient for practical use, and it has many advantages, such as being relatively easy to recover.

(Object of the invention) The present invention was made in order to take advantage of the advantages of such an unsaturated polyester resin composition while eliminating the drawbacks of the conventional technology. Another object of the present invention is to provide an unsaturated polyester resin composition for cathode ray tube processing that does not cause curing distortion during curing.

(Means for Solving the Problems) The present invention is produced by reacting an acid component containing an unsaturated dibasic acid and/or its acid anhydride, and optionally other polybasic acid with an alcohol component. An unsaturated polyester having a molecular weight of 500 to 8000 per mole of unsaturated groups is added to styrene and/or its derivatives and acrylic acid, methacrylic acid and/or its derivatives, depending on the number of moles of unsaturated groups in the unsaturated polyester. (a), the number of moles of unsaturated groups in styrene and/or its derivatives is (b), and the number of moles of unsaturated groups in acrylic acid, methacrylic acid and/or its derivatives is (c). a)
/ ((b)+1c)) = 1/30 to t/1 and (b)/(c) = 1/10 to 10/1 unsaturated polyester resin composition for cathode ray tube processing. Regarding.

Examples of the unsaturated dibasic acid and/or its acid anhydride used in the unsaturated polyester of the present invention include maleic acid, fumaric acid, and itaconic acid.

Examples include ntraconic acid and maleic anhydride. Two or more of these may be used in combination.

Other polybasic acids that may be used as necessary in the present invention include phthalic acid and phthalic anhydride.

Isophthalic acid, terephthalic acid, trimellitic acid.

Trimellitic anhydride, succinic acid, azelaic acid.

Adipic acid, tetrahydrophthalic acid, tetrahydrophthalic anhydride, hexahydrophthalic acid, hexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, anthracene-maleic anhydride adduct, rosin-maleic anhydride adduct, het acid, het anhydride Examples include fluorinated polybasic acids such as tetrachlorophthalic acid and tetrachlorophthalic anhydride, and halogenated polybasic acids such as tetrabromophthalic acid and tetrabromophthalic anhydride. These may be used in combination for two or more harvests.

The alcohol component is ethylene glycol.

Diethylene glycol, phlopylene gelicol.

Diglobylene glycol, 1,3-butanediol.

1,4-butanediol, 2,3-butanediol.

Dihydric alcohols such as 1.5-bentanediol, 1.6-hexanediol, triethylene glycol and neopentyl glycol, trihydric alcohols such as glycerin and trimethylolpropane, and tetrahydric alcohols such as pentaerythritol may be used. I can do it.

It is also possible to use halogenated alcohols such as chlorinated and brominated alcohols.

The production method for producing unsaturated polyester by reacting the acid component and alcohol component described above is mainly carried out by proceeding with a condensation reaction, and low molecules such as water produced when the first component reacts are removed from the system. Proceed by letting go.

The reactor used for this reaction consists of an inert acid component such as glass or stainless steel, and a stirring device. In order to prevent distillation of alcohol components due to azeotropy of water and alcohol components, we installed a heating device to increase the temperature of the fractionator 2 reaction system, an eccentricity control circuit for this heating device, and a blowing device for nitrogen gas, etc. Preferably, a reactor is used.

As for the reaction conditions, it is preferable to carry out the reaction at a temperature of 150°C or higher at which the rate of one reaction is sufficiently high. In order to prevent coloring due to oxidation reactions at high temperatures, the temperature range is more preferably from 160°C to 210°C.

Furthermore, in order to prevent side reactions due to oxidation at high temperatures, it is preferable to carry out the synthesis while passing an inert gas such as nitrogen or carbon dioxide.

The reaction proceeds by heating a system in which an acid component and an alcohol component are mixed, and removing low-molecular compounds such as condensed water produced from the system. This is preferably carried out by passing an inert gas through a natural reservoir, or This is done using a vacuum reservoir. Further, if the low molecular weight compound to be stored has a boiling point, a high vacuum is required.

Furthermore, in order to promote the accumulation of low-molecular compounds such as condensed water, a solvent such as toluene or xylene can be added to the system as an azeotropic component to perform natural accumulation.

The progress of the reaction can generally be determined by measuring the volume of the reservoir produced by the reaction, quantifying the terminal functional groups, and measuring the viscosity of the reaction system.

The unsaturated polyester used in the present invention is:

It has a molecular weight of 500 to 80,000 per mole of unsaturated group, and 1000 to 40,000 per mole of unsaturated group.
A range of molecular weights is preferred.

Such an unsaturated polyester can be manufactured by a known method by adjusting the blending ratio of materials.

The molecular weight per mole of unsaturated groups in unsaturated polyester is 5.
If it is smaller than 00, the crosslinking density of the cured resin product will be high, and therefore the shrinkage rate of the resin will be large, and the cured resin product will not be soft.

This may cause peeling failure from the front glass or cathode ray tube face plate.

The molecular weight per mole of unsaturated groups in unsaturated polyester is 8.
If it exceeds 000, sufficient cross-linking does not occur during resin curing, resulting in copolymerization of styrene and/or its derivatives, acrylic acid, methacrylic acid and/or its derivatives, and the cured resin becomes cloudy. However, it cannot be used as a component for cathode ray tubes.

In addition, because bridging does not occur sufficiently,
, 90 cm, R, H,), the adhesion strength with the front glass or cathode ray tube face plate portion decreases, causing peeling.

In the present invention, styrene and/or its derivatives include styrene and p-methylstyrene.

α-methylstyrene, divinylbenzene, chlorostyrene, dichlorostyrene, vinyltoluenate can be used. These can be used alone or in combination.

In the present invention, acrylic acid, methacrylic acid and/or derivatives thereof include acrylic acid.

Allyl acrylate, benzyl acrylate, butyl acrylate, ethyl acrylate, methyl acrylate, propyl acrylate, hydroxyethyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, propyl methacrylate, methacrylic acid Allyl, Hensyl methacrylate, Hydroxyethyl methacrylate.

Dodecyl methacrylate, octyl methacrylate.

Pentyl methacrylate and the like can be used. These can be used alone or in combination.

In the present invention, the number of moles of unsaturated groups in the unsaturated polyester is (a), the number of moles of unsaturated groups in the styrene monomer and /l or its derivatives is (b), acrylic acid, methacrylic acid and / or when the number of moles of unsaturated groups in the derivative thereof is (c), la)/((b)+(c)
) is 1/30 to 1/l and (b)/(c) is 10/
It is used in the range of 1 to 1/10, but (a)/((b
l+(c)) is 1715 to 1/2, and (b)/
(c) is preferably in the range of 8/1 to 1/8.

If the ratio of (al/(b)+(c)) is smaller than 1/30, curing tends to be uneven when curing the unsaturated polyester resin composition for bonding the front glass of cathode ray tubes. This causes distortion and stripes or bright spots appear on the screen, which impairs the product's value.

On the other hand, when the ratio of (at/((b)+(cl)) is greater than 1/1, the viscosity reducing effect of styrene and/or its derivatives or acrylic acid, methacrylic acid and/or its derivatives is Gone.

This makes the injection work of the unsaturated polyester resin composition extremely difficult, which not only leads to a decrease in workability such as poor foam film damage during mixing and injection of the curing agent, but also causes striped patterns.

Further, if the ratio Tb)/(c) is larger than 10/1 or smaller than 1/10, bright spots are likely to occur and the commercial value will be impaired.

In the present invention, unsaturated polyester may be dissolved in a mixture of styrene and/or its derivatives and acrylic acid, methacrylic acid and/or its derivatives; After dissolving, acrylic acid, methacrylic acid and/or a derivative thereof may be added.

Conversely, an unsaturated polyester may be dissolved in acrylic acid, methacrylic acid and/or a derivative thereof, and then styrene and/or a derivative thereof may be added.

The unsaturated polyester resin composition prepared in this manner can be prepared by adding hydroquinone, pyrocatechol, 2
．． After adding a polymerization inhibitor such as 6-di-tert-butyl para-cresol, it can be cured by K such as organic peroxide catalysts such as methyl ethyl ketone peroxide, benzoyl peroxide, cumene hydroperoxide, and lauroyl peroxide. I can do it.

In addition, these organic peroxide catalysts include metal soaps such as naphthene, cobalt acid, and cobalt octenoate, quaternary ammonium loadings such as dimethylpentylammonium chloride, β-diketones such as acetylacetone, dimethylaniline, N- It can be used in combination with a curing accelerator such as amines such as ethyl metatoluidine and triethanolamine.

In addition, the unsaturated polyester resin composition according to the present invention is
As a photopolymerization initiator, for example, di-7-enyl disulfite, benzine, benzine methyl ether, benzoin ethyl ether, benzoin-n-propyl ether,
Benzoin isopropyl ether, benzoin 3cc-
Butyl ether.

Photocuring can also be performed using benzoin-2-pentyl ether, benzoin cyclohexyl ether, dimethylbenzyl ketal, or the like.

The above organic peroxides and these photopolymerization initiators may be used in combination.

The resin composition of the present invention may also contain a dye, plasticizer, and ultraviolet absorber, if necessary.

The unsaturated polyester resin composition of the present invention is injected between the front glass and the face plate of cathode ray tubes such as television cathode ray tubes and computer display tubes, and is cured. ,
There are infrared curing, electron beam curing, heat curing, room temperature curing, etc., and curing may be performed by each method alone or by a combination of these methods.

(Example) The present invention will be explained below with reference to Examples.

Parts indicate parts by weight.

Examples 1, 2.3 A 31-meter four-way flask was equipped with a stirring bar, a condenser, a nitrogen gas inlet tube, and a thermometer.

Diethylene glycol 1166 parts Adipic acid
584 parts phthalic anhydride
740 parts fumaric acid 116
The temperature was raised to 150° C. in 1.5 hours using a mantle heater while slowly flowing nitrogen gas.

Furthermore, the temperature was raised to 200° C. over 4 hours and kept at that temperature. An unsaturated polyester (A) having an acid value of 34 was obtained in about 10 hours. After further lowering the temperature to 100° C. and adding 0.3 parts of hydroquinone as a double polymerization inhibitor, the unsaturated polyester was poured out onto a stainless steel vat and allowed to cool to room temperature. The resulting unsaturated polyester had a molecular weight of 24,400 per mole of unsaturated groups.

This unsaturated polyester was dissolved in a mixture of styrene and methyl methacrylate according to the formulation shown in Table IK.

Cobalt octenoate (metal content: 6% by weight) was added to 200 parts of the obtained unsaturated polyester resin composition.

0.1 part (manufactured by Dainippon Ink & Chemicals) and 2 parts of methyl ethyl ketone peroxide (manufactured by NOF Corporation) were added.

On the other hand, thickness 3aa++X 250mmX 250m+a
on transparent flat glass, thickness 3×250am×25
A 240 aa x 240 am hole was cut out from the inside of the 0 am+ silicone plate, leaving the periphery, and a silicone plate with a slit injection port was placed in one place around the remaining periphery as a spacer. Thickness 3 on top of this spacer
A transparent flat glass plate measuring 250 mm x 250 mm was placed, and the glass plates were fastened with a stopper to obtain a casting jig. The above unsaturated polyester resin composition was injected through the slit injection port of the spacer between the casting jigs.

Thereafter, the resin was left in an electric dryer at 80° C. for 30 minutes to harden the resin, thereby obtaining an unsaturated polyester resin cast plate.

Table 1 shows the properties of the casting plate thus obtained.

As Comparative Examples 1 and 2, compositions having the formulations shown in Table 1 were prepared using the unsaturated polyesters (5) of Examples 1 and 2.3, and the characteristics of the casting plates were examined in the same manner.

In Examples 1, 2.3, there was no curing distortion during curing, and no striped patterns or bright spots were observed.

However, in Comparative Examples 1 and 2, no striped pattern was observed, but bright spots were generated.

In Table 1, the curing strain was visually observed to determine the presence or absence of striped patterns.
The number of bright spots was counted (same as in Table 2).

Examples 3, 4.5 3I with the same equipment as Example 1! In a Yotsuro flask.

Diglopyrene glycol 1474 parts Adipic acid
1241 parts maleic anhydride
147 parts were charged, and the temperature was raised to 150° C. in 1 hour using a mantle heater while slowly flowing nitrogen gas. Furthermore, the temperature was raised to 200° C. over 4 hours and kept at that temperature. After about 12 hours, an unsaturated polyester (B) having an acid value of 25 was obtained.

The temperature was further lowered to 100°C, and 0.3 parts of hydroquinone was added as a double polymerization inhibitor, and the unsaturated polyester (Bl) was poured out into a stainless steel vat.

It was left to stand at room temperature and cooled.

This obtained unsaturated polyester (B) has 1 unsaturated group
The molecular weight was 1710 per mole.

This unsaturated polyester was dissolved in a mixture of styrene and butyl acrylate according to the formulation shown in Table 2.

Table 2 shows the properties of the casting plate obtained by curing the unsaturated polyester resin composition in the same manner as in Example 1.

No curing strain was observed in Examples 4, 5.6.
Below: (1) The unsaturated polyester resin composition of the present invention significantly reduces curing distortion, especially bright spots, which occurs in conventional unsaturated polyester resin compositions, and is suitable as a resin composition for cathode ray tube processing. It is something.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a cathode ray tube with a front glass. Explanation of symbols 1...Cathode ray tube 2...Face plate portion 3...Front glass 4...Tape 5...
Resin composition 6... Cathode ray tube with front glass

Claims (1)

[Claims] 1. 1 mole of unsaturated groups obtained by reacting an acid component containing an unsaturated dibasic acid and/or its acid anhydride, and optionally other polybasic acid with an alcohol component. 500 per hit
An unsaturated polyester having a molecular weight of ~8000 is combined with styrene and/or its derivatives and acrylic acid,
For methacrylic acid and/or its derivatives, the number of moles of unsaturated groups in unsaturated polyester (a) and the number of moles of unsaturated groups in styrene and/or its derivatives (b)
, when the number of moles of unsaturated groups in acrylic acid, methacrylic acid and/or its derivatives is (c), (a)/
{(b)+(c)}=1/30 to 1/1 and (b)/
(c) An unsaturated polyester resin composition for cathode ray tube processing, which is dissolved in the range of 1/10 to 10/1.